The Nature of Disease p98

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The Nature of Disease p98

• Chapter 39.1

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P98 Nature of Disease

• Warm up Have you ever had an infection? Describe
  what it was like.
• Disease a change that disrupts the normal
  functioning of the body
• Infectious Disease caused by the presence of
  pathogens in the body.
• Pathogens can be
• Bacteria, Protozoans,
• Fungi, Viruses, Parasites

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P 98 Sources of Pathogens

• Soil
• Contaminated water
• Infected animals
• Other people
• Some diseases are inherited from DNA and are not
  contagious
• Hemophilia
• Sickle Cell Anemia

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P 98 4 Ways Pathogens are transmitted

• Direct contact
• skin, body fluids
• By an object
• Food poisoning
• Through the Air
• dust particles
• By an intermediate organism (vector)
• Malaria mosquitoes

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Patterns of Disease p98

• Epidemic a disease that found among many people
  in an area
• Bird flu, SARS (Asia)
• Mad cow (England)
• Ebola (Africa)
• Pandemic a global epidemic
• Influenza
• HIV-AIDS

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• Treatments
• Antibiotics will kill or inhibit the growth of
  fungus or bacteria.
• With misuse, bacteria will become resistant to
  them!
• DO NOT AFFECT VIRUSES!

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Defense Against Infectious Diseases p100

• Chapter 39.2

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P 100 Homeostasis
Warm up What are things you can do to stay
healthy? Homeostasis When the body is well and
working properly

• Stress
• Lack of sleep
• Alcohol use
• Drug use
• Smoking
• Dehydration
• Unhealthy diet

• Disrupt Homeostasis and prevent your body from
  fighting off disease.

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Maintaining Homeostasis p100

• Lymphatic System
• Cleanses the cells of pathogens and carries them
  out of the body.
• The lymph glands collect the dirty fluid and
  filter it.
• Ex Tonsils

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Innate Immunity p100

• 1st line of defense against pathogens
• Skin Creates a physical barrier
• Body secretions
• Mucus
• Sweat
• Tears
• Saliva

have the enzyme lysozyme that kills some bacteria
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Innate Immunity Cells p100

• When a pathogen invades or an area is injured,
  inflammation occurs to bring fluids to area.
• Phagocytes white blood cells that surround and
  kill pathogens
• Macrophages white blood cells that are first
  responders to defend tissue, big eaters
• Interferons proteins that protect cells against
  viruses by making cells produce antiviral
  proteins.
• Pus a collection of live and dead white blood
  cells and pathogens that collect at the infected
  site.

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Acquired(Adaptive) Immunity p102

• Warm up explain what innate immunity is and give
  2 exmples.
• When our White Blood Cells get attacked by a
  pathogen, they make antibodies for them while
  they fight them off.
• These stay in our bodies and alerts the immune
  system to kill off the pathogen if it ever comes
  back.

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Acquired Immunity cells p 102

• Antigens are markers on foreign bodies that are
  recognized by our lymphatic system.
• At lymph nodes, lymphocytes will recognize and
  kill foreign body.
• In blood, Helper T cells can bind to macrophages
  to help it recognize and bind to pathogen to kill
  it.
• B cells in blood bind to T cells and become
  plasma cells that make more antibodies that help
  to remember the pathogen so it can kill it faster
  next time.
• Cytotoxic T cells can also kill pathogens.

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Passive Acquired Immunity p102

• Acquiring antibodies made by someone else
• From the mother to baby
• through the placenta milk
• Vaccines injection of weakened pathogens so
  your immune system can make antibodies.